import tkinter as tk
from tkinter import Entry
# Next Form which open when we click on the register button
def register ():
    window = tk.Tk()
    window.title("GUI")
    label = tk.Label(window, text="Enter Username").pack()
    #u=StringVar()
    global username
    global password
    username=Entry(window)
    #print(u)
    username.pack()
    label = tk.Label(window, text="Enter password").pack()
    password=Entry(window,show='*')
    password.pack()
    button3=tk.Button(window,
                      text="OK",
                      command=ok)
    button3.pack(side=tk.LEFT)
    button4=tk.Button(window,
                      text="Cancel",
                      command=quit)
    button4.pack(side=tk.LEFT)
def ok():
    
 print("code here to click on Ok button in register page")

root = tk.Tk()
frame = tk.Frame(root)
frame.pack()

button1 = tk.Button(frame,
                   text="Login",
                   fg="blue")
            
button1.pack(side=tk.LEFT)
button2 = tk.Button(frame,
                    text="Register",
                    command=register)
button2.pack(side=tk.LEFT)

root.mainloop()